# Copyright (c) 2011 Andrea Spadaccini <andrea.spadaccini@gmail.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.

"""Various utility functions"""

__author__ = "Andrea Spadaccini"
__license__ = "GPL v3 or later"
__email__ = "andrea.spadaccini@gmail.com"

__all__ = ["urllib_fetch", "urlfetch_fetch"]

# One of the following two functions will be conditionally imported by the
# rest of the program, according to the context (local test or deploy to GAE).
#
# Note that even if the import statement is executed multiple times while the
# program is running, the module is imported only once.
def urllib_fetch(url):
    """An HTTP fetch function based on urllib2, used when testing the system
    in local, without deploying to GAE"""
    import urllib2
    opener = urllib2.build_opener()
    opener.addheaders = [('User-agent', 'Mozilla/5.0')]
    f = opener.open(url)
    data = f.read()
    f.close()
    return data

def urlfetch_fetch(url):
    """HTTP fectch function based on GAE urlfetch module."""
    from google.appengine.api import urlfetch
    return unicode(urlfetch.fetch(url).content, 'utf-8')
